Thanks EE Times for the interesting topic. Controlling the electrical percolation threshold can also be done biologically by "binding of antigens to the antibodies, disrupt the network continuity causing increased resistance of the network," here is the link:
http://pubs.acs.org/doi/abs/10.1021/ac902644z
What would be neat (either in biologic or non-biologic versions) is to further control the conductivity dynamically either thru voltage or temperature bias.
MP Divakar

Peter, programs for 2011 and 2012 have been posted (www.cmoset.com). We would be delighted if you can come to Whistler in 2011 or Vancouver in 2012, I will arrange registration waiver ($500 value)...Kris